NERVOUS SYSTEM. 805 



them is rugose and plicated. The orifice leading to this pouch is small, 

 and opens in front of the prepuce. 



Fig. 405. 



a 



Sexual organs of male Beaver. 



(2355.) Lastly, in connexion with these odoriferous glands we may 

 mention the " temporal glands" of the Elephant, from the duct of 

 which, situated on each side midway between the eye and the ear, there 

 flows a viscid and fetid liquid ; and likewise the " anal glands " met 

 with in most Carnivora. The ducts of the glands last mentioned open 

 near the margin of the anus ; and in some genera, as the Skunk and 

 the Polecat, the stench produced by the fluid poured from these sources 

 is so intolerable as to become a most efficient defence against a foreign 

 enemy. 



(2356.) We now come to consider the nervous system of the MAM- 

 MALIA, and are of course prepared to anticipate that in proportion as 

 they surpass all other animals in intelligence, so will the encephalic 

 masses assume a complexity and perfection of structure such as we 

 have not hitherto witnessed in the whole series of the animal creation. 

 Their senses likewise may be presumed to have attained the utmost 

 delicacy of organization, in correspondence with the exalted attributes 

 conferred upon this important class, and consequently to exhibit append- 

 ages and accessory parts adapting them most accurately to repeat to the 

 sensorium impressions derived from without. 



(2357.) Abstruse as the study of the brain has been rendered by the 



